Fabrics with intelligence capabilities, such as the ability to monitor physiological body vital signs, or fabrics used to warm or heat the body (e.g., electric blankets), require conductive elements to be embedded in the fabric. Typical conventional fabrics weave or knit the conductive elements into the fabric. Weaving interlaces the weft threads (the horizontal threads) and the warp threads (lengthwise, or perpendicular to the weft) on a loom, while knitting intertwines yarn or thread in a continuous series of connected needle loops on a machine.
U.S. Patent No. 6,145,551, incorporated by reference herein, discloses a weaving process to produce a woven garment with intelligence capability by weaving non-elastic conductive fibers, such as wires made of copper, stainless steel, and the like, or plastic optical fibers into the fabric. Because the non-elastic conductive wires or fibers are woven into the fabric, the fabric has little or no elongation capability. Hence, any garment produced from this fabric cannot stretch and therefore lacks a tight, body conforming fit. Attaching sensors (e.g., electrodes) related to the monitoring of physiological body vital signs to the loose fitting garment produced from this design results in inaccurate readings because the garment lacks tight closure to the body. Because this fabric is constructed by weaving a series of conductive wefts and warps the embedded conductive wires are employed in a grid configuration. The grid design suffers from the distinct drawback that electrical insulation is required at all the cross points of the grid to prevent electrical short circuiting. Moreover, the weaving machine, or loom employed to produce this fabric is very cumbersome and expensive.
U.S. Patent No.6,381,482, incorporated by reference herein, produces a woven or knitted fabric with an electrical conductive component which may be used for intelligence capabilities. In one design of the '482 patent, a knitted construction is used with conductive wires in-laid between a series of connected needle loops of the yarn. Because the in-laid wires are non-elastic, this type of knit construction, similar to the above, produces a garment which lacks a tight, body conforming fit. The '482 patent also utilizes only insulated electrical wire (e.g., insulated with PVC or polyethylene) which further adds to the rigidity and poor bending capabilities of the garment, resulting in a rigid, stiff fitting, uncomfortable garment which further reduces the accuracy of sensors connected to the conductive elements of the garment.
U.S. Patent Nos. 6,501,055, 6,414,286, 6,373,034, 6,307,189, 6,215,111, and 6,160,246, all incorporated by reference herein, hereinafter “the Maiden Mills patents”, disclose electric heating/warming fabric articles employed in electric blankets. The fabrics produced by the Malden Mills patents utilize a tubular knit construction, wherein a fabric body is produced which includes a technical face formed by the stitch yarn and a technical back formed from the loop yarn in a reverse plated knit construction. The process is designed to raise the yarn on both sides of the technical face and/or technical back without breaking the conductive wires. Electrical resistance heating elements (e.g., conductive wires) are incorporated in the tubular fabric as a part of the stitch yarn at a predetermined spacing from each other. Because the electric blankets manufactured by the Maiden Mills patents require thermal and electrical insulative properties, the fabric body is raised by napping, sanding, or brushing to generate fleece. The napping process requires the tubular knit fabric to be cut longitudinally in order to nap the technical face and/or technical back. Incorporation of stretchable yarn into the Malden Mills patent, which utilizes wire brushes and the like, would destroy any conductive material incorporated into the fabric. Hence, the fabric of the Malden Mills patents lacks any significant stretching capabilities. The napping process also obstructs access to the conductive wires incorporated into the fabric thus preventing easy attachment of sensors to the conductive wires. Moreover, longitudinally cutting the tubular fabric also destroys the continuity of the embedded conductive wires which results in the requirement of a bus to interconnect the conductive elements. Furthermore, the Maiden Mills patents cannot manufacture body size or seamless garments.